In order to perform centralized management of data extending over multiple external storage systems, for example, multiple disk subsystems, the configuration information of each system is acquired and the whole configuration in which the whole system was integrated needs to be defined. Here, the configuration information, includes, for example, setting concerning an internal access path of a disk subsystem, a logical unit, the capacity or access authority of the logical unit and data move, setting concerning data copying between the disk subsystems, setting or acquisition of a performance control mode or performance data, setting of a maintenance method and a fault or user operation event.
In the past, system administrators periodically collected the configuration or performance of a disk subsystem, fault, expansion and other events (hereinafter referred to as events) that will occur under the system using software that a host computer (hereinafter merely referred to as a host) which uses the disk subsystem manages. That is, a system administrator had to connect the host computer to each disk subsystem and acquire the configuration information of these systems, then provide the definition and necessary setting of the whole system configuration using management software by manual operation.
An art for displaying in mapping mode that a logical volume that can access a disk subsystem from a host corresponds to which physical unit of the disk subsystem is disclosed in U.S. Pat. No. 5,973,690. However, there is no suggestion concerning transverse management between multiple disk subsystems.
In order to define the whole configuration in which the whole system was integrated, desirably, a system administrator should collectively perform setting that extends over between the multiple disk subsystems. This is because the configuration of the whole system is defined more easily than it is defined every disk subsystems and the number of times the configuration is checked and redefined is reduced, thereby reducing artificial misoperation. This is because the system operation can also be improved if the setting that extends over between the multiple disk subsystems is performed collectively.
The state is considered in which a certain user A installs a database and another application A in a host computer and multiple disk subsystems are used as an external storage system. Because the size of the file that the application A of the user A uses was reduced, a system administrator S of this external storage system is assumed to have added a logical unit (LU) to a disk subsystem.
However, the disk subsystem may also use another application B (higher performance than for the application A is requested) that the user B uses in another host.
In such case as this, if the added logical unit should have shared a physical resource (physical unit) with a logical unit allocated so that the application B that requests high performance can use it, the addition of this logical unit is affected and performance degradation will be caused concerning the execution of the application B in which importance is attached to the performance.
In other words, although the addition of the logical unit that the system administrator S made and that was made for the user A is a measure for maintaining and increasing the execution of the application A of the user A, the measure will cause degradation of the execution performance of the application B, and is eventually said to be artificial misoperation when it is viewed from the performance aspect of the whole system.
A system administrator normally monitors the performance of an application using a performance monitoring tool. Because the performance monitoring tool monitors the process operating state of the application or the read and write performance of the file that the application uses, a cause in which the addition of the previous logical unit gave rise to the performance degradation of another application cannot be ascertained.
With the sudden spread of the Internet, access requests from many client terminals increase. These access requests are regarded as access from multiple hosts. A storage system that integrates these many types of access also requires a measure that follows the demand of data size, and the opportunity of logical unit expansion in an individual disk subsystem is increasing constantly. It is desired to predict when the logical unit that corresponds to the file that a business-related application uses exceeds a usable capacity and arrange a schedule of planned logical unit expansion. Accordingly, an increasing tendency toward the file size, the position of the logical unit in which the file was stored and the usable capacity are investigated, and the schedule must be arranged from these relationships.
In the prior art, although these pieces of information were collected individually and periodically, there is no means for building these relationships. The measure is no more than a measure that depends on an empirical rule of a system administrator, and the above prediction and planning were very difficult.